A method and system of effervescent atomization of liquid fuel for a rotating detonation combustor (RDC) for a propulsion system is provided. The method includes flowing liquid fuel through a fuel injection port of a nozzle assembly of the RDC system; flowing a gas through the fuel injection port of the nozzle assembly volumetrically proportional to the liquid fuel; producing a gas-liquid fuel mixture at the fuel injection port by mixing the flow of gas and the flow of liquid fuel; flowing an oxidizer through a nozzle flowpath of the RDC system; producing an oxidizer-gas-liquid fuel mixture by mixing the gas-liquid fuel mixture and the flow of oxidizer within the nozzle flowpath; and igniting the oxidizer-gas-liquid fuel mixture within a combustion chamber of the RDC system.

CERMET fuel element includes a fuel meat of consolidated ceramic fuel particles (preferably refractory-metal coated HALEU fuel kernels) and an array of axially-oriented coolant flow channels. Formation and lateral positions of coolant flow channels in the fuel meat are controlled during manufacturing by spacer structures that include ceramic fuel particles. In one embodiment, a coating on a sacrificial rod (the rod being subsequently removed) forms the coolant channel and the spacer structures are affixed to the coating; in a second embodiment, a metal tube forms the coolant channel and the spacer structures are affixed to the metal tube. The spacer structures laterally position the coolant channels in spaced-apart relation and are consolidated with the ceramic fuel particles to form CERMET fuel meat of a fuel element, which are subsequently incorporated into fuel assemblies that are distributively arranged in a moderator block within a nuclear fission reactor, in particular for propulsion.

A method for operating a rotating detonation engine, having a radially outer wall extending along an axis; a radially inner wall extending along the axis, wherein the radially inner wall is positioned within the radially outer wall to define an annular detonation chamber having an inlet and an outlet, wherein the method includes flowing liquid phase fuel along at least one wall of the radially inner wall and the radially outer wall in a direction from the outlet toward the inlet to cool the at least one wall and heat the liquid fuel to provide a heated liquid fuel; flowing the heated liquid fuel to a mixer at the inlet to reduce pressure of the heated liquid fuel, flash vaporize the heated liquid fuel and mix flash vaporized fuel with oxidant to produce a vaporized fuel-oxidant mixture; and detonating the mixture in the annular detonation chamber.

A pulse combustor system for reducing noise and/or vibration levels. The system includes a pulse combustor including a combustion chamber, an inlet pipe, an exhaust pipe, and a first fuel injector for injecting fuel into the combustion chamber. The pulse combustor has a fundamental oscillation mode and one or more additional oscillation modes. The system includes at least one pressure sensor for measuring a pressure inside the fuel combustor and/or a at least one fluid velocity sensor for measuring fluid velocity at the inlet pipe or at the exhaust pipe. A controller adjusts a rate of fuel supply to the pulse combustor if the measured pressure and/or the measured velocity is above a predetermined threshold value to reduce excitation of the one or more additional oscillation modes.

A pulse combustor system for reducing noise and/or vibration levels. The system includes a pulse combustor including a combustion chamber, an inlet pipe, an exhaust pipe, and a first fuel injector for injecting fuel into the combustion chamber. The pulse combustor has a fundamental oscillation mode and one or more additional oscillation modes. The system includes at least one pressure sensor for measuring a pressure inside the fuel combustor and/or a at least one fluid velocity sensor for measuring fluid velocity at the inlet pipe or at the exhaust pipe. A controller adjusts a rate of fuel supply to the pulse combustor if the measured pressure and/or the measured velocity is above a predetermined threshold value to reduce excitation of the one or more additional oscillation modes.

A ram-jet and turbo-jet detonation engine includes an inlet part and a discharge part both shaped as axis-symmetrical round hollow rotating cones interconnected by a narrow middle part, having vanes, mounted on the internal surfaces of the cones, not completely overlapping a central part of a channel, and form spirals, twisted about a common central axis of the channel. The inlet cone with vanes serves as a ventilator/compressor, and the discharge cone with vanes serves as a turbine and discharge nozzle. The middle part and the discharge cone are built as one integral component. A centripetal pump supplies fuel to a mixing section. The engine includes a firing system, generating short high-voltage electrical pulses, providing for burning of combustible mixture in a detonation mode. The invention enables an independent horizontal take-off of flying apparatus and a possibility of varying/alternating the speed within a range from subsonic to hypersonic.

A ram-jet and turbo-jet detonation engine includes an inlet part and a discharge part both shaped as axis-symmetrical round hollow rotating cones interconnected by a narrow middle part, having vanes, mounted on the internal surfaces of the cones, not completely overlapping a central part of a channel, and form spirals, twisted about a common central axis of the channel. The inlet cone with vanes serves as a ventilator/compressor, and the discharge cone with vanes serves as a turbine and discharge nozzle. The middle part and the discharge cone are built as one integral component. A centripetal pump supplies fuel to a mixing section. The engine includes a firing system, generating short high-voltage electrical pulses, providing for burning of combustible mixture in a detonation mode. The invention enables an independent horizontal take-off of flying apparatus and a possibility of varying/alternating the speed within a range from subsonic to hypersonic.

A Brayton cycle engine including a longitudinal wall extended along a lengthwise direction. The longitudinal wall defines a gas flowpath of the engine. An inner wall assembly is extended from the longitudinal wall into the gas flowpath. The inner wall assembly defines a detonation combustion region in the gas flowpath upstream of the inner wall assembly.

A Brayton cycle engine including a longitudinal wall extended along a lengthwise direction. The longitudinal wall defines a gas flowpath of the engine. An inner wall assembly is extended from the longitudinal wall into the gas flowpath. The inner wall assembly defines a detonation combustion region in the gas flowpath upstream of the inner wall assembly.

A Brayton cycle engine including a longitudinal wall extended along a lengthwise direction. The longitudinal wall defines a gas flowpath of the engine. An inner wall assembly is extended from the longitudinal wall into the gas flowpath. The inner wall assembly defines a detonation combustion region in the gas flowpath upstream of the inner wall assembly.